The Fungal Inquisition

The mission of Symbiogenics is based on two fundamental observations:1) All plants in natural ecosystems are thought to be symbiotic with microscopicfungi (known as fungal endophytes) that live inside plant tissues.

2) Contrary to contemporary views, we have found that in natural ecosystems it is the fungal endophytes that adapt plants to environmental stresses ratherthan the plants themselves. Based on these observations, we have developed a non-GMO strategy for generating plants of virtually any crop or native species that can tolerate drought, high salinity, extreme temperature or toxic chemical stress. Although we have made great advances in symbiogenic technology, there is still much to be discovered about symbiosis and sustaining plant life on earth. Many questions need to be addressed such as:

1) What are the limits of fungal endophyte-conferred stress tolerance?2) Are there extreme environments where plants do not associate with fungal endophytes?3) What are the molecular, genetic and biochemical bases of the symbiotic interaction responsible for stress tolerance?4) How do environmental gradients affect the relationship between plants and fungal endophytes? 5) What is the communication between plants, fungal endophytes and other soil microorganisms?6) How does habitat degradation influence the abundance and diversity of fungal endophytes and other soil microorganisms?7) How will climate change affect symbiotic relationships and soil microbial communities?

Based on these questions and others, we are focusing on the research areas below to address global issues concerning agriculture and the natural environment. The goal of these projects is to ensure sustainability in agricultural and natural systems, and reduce human suffering in the 21st century.

Mitigating Impacts of Climate Change

Although significant scientific effort has focused on reducing greenhouse gases and modeling potential impacts of climate change on aquatic and terrestrial habitats, comparatively little has been invested into mitigating the impacts of climate change on biological communities or determining the adaptive potential of the organisms at risk. Climate models predict that plants in natural and managed ecosystems will face increased drought, soil salinity, atmospheric CO2 and temperature fluctuations (Copenhagen Diagnosis). In addition, positive feedback loops are expected to significantly increase the frequency of wildfires, which will further increase atmospheric CO2 levels. Climate predictions will allow land managers to assign levels of risk to areas and habitats under their purview in order to prioritize restoration efforts and determine potential impacts on threatened and endangered species. However, there are few, if any, tools available to resource managers for sustaining plant communities threatened by these climate-induced stresses. Sustaining vegetation is required to sustain animal communities in terrestrial, riparian and marine habitats.

The restoration of degraded habitats is a time-consuming and expensive endeavor. In addition, restoration success rates are difficult to determine because it can take quite a while before restoration is realized. Habitat re-vegetation efforts commonly involve plants and/or seeds that are generated in nurseries under conditions favoring plant growth and reproduction. We have found that under these conditions plants lose the fungal endophytes required for adaptation to the habitats into which they will be transplanted or seeded during restoration efforts. We have developed methods to re-introduce endophytes into plant seeds to improve seedling establishment and growth. We are undertaking research to propagate plants under conditions that maintain their natural endophytes so that symbiotic plants can be transplanted. In addition, we are developing strategies to increase seed shelf life and germination rates. In the near future we will be ready to begin testing our methods for restoration efforts.

Invasive Species

Although only a small percentage of plant species become invasive when moved to non-native habitats, it is not yet possible to predict if a plant will become invasive because there are no known mechanisms to explain invasiveness. Often, invasive plants chemically engineer the soil environment creating a habitat incompatible with native species. We have discovered that both native and invasive plants require fungal endophytes for seedling establishment and stress tolerance, and hypothesize that invasive plants also require endophytes to tolerate the chemical environment they engineer. We are undertaking research to test this hypothesis and develop new tools for resource managers to control invasive plants.

Sustainable Agriculture

The greatest threats to agricultural sustainability are drought, increasing temperatures and soil salinization, all of which are being exacerbated by climate change. Historically, three approaches have been taken to develop stress tolerant plants: genetic modification (GMO), mutation selection and selective breeding of traits from wild plants. However, these efforts have had limited field success presumably because 1) stress tolerance involves genetically complex processes and 2) the ecological and evolutionary mechanisms responsible for plant stress tolerance are poorly defined.

The realization that plants in high-stress habitats depend on fungal endophytes for stress tolerance prompted us to begin developing a strategy for generating stress tolerant plants using fungal endophytes. We refer to this technology as symbiogenics (symbio for symbiosis and genic for gene influence). Depending on the fungal endophyte, plants are also protected from bacterial and fungal diseases. Remarkably, we have found that endophytes can communicate with crop plants similarly to what they do with the native plants from which they were isolated. Endophytes also have profound effects on the growth, development and physiology of plants. For example, endophyte colonized seedlings grow faster, develop larger shoots and root systems, and consume up to 50% less water than plants without endophytes.

We believe symbiogenics is a viable strategy for sustainable agriculture because rather than moving individual genes, we do what mother nature has done for eons - move entire genomes by moving endophytes.

Symbiotic Communication

To optimize plant-fungal combinations for specific needs, we are characterizing the molecular, genetic and biochemical bases of the symbiotic communication responsible for endophyte conferred stress tolerance. This information will allow us to develop diagnostic tools to 1) properly match specific endophytes and plants to achieve desired stress tolerances and 2) breed plants for optimal symbiotic communication to maximize stress tolerance.

Basic research is being performed with rice and tomato plants because they represent monocot and eudicot plants, and both are major food crops. Genome sequences are available for both species and many varieties of each plant have active breeding programs with which to collaborate.